DE 10 2007 018 618 A1 describes the widely known construction of a turbocharger for an internal combustion engine. This turbocharger consists essentially of a radial turbine with a turbine wheel and of a radial compressor coupled to the turbine wheel by a shaft and having a compressor impeller. The turbine wheel is driven by the exhaust-gas flow from the internal combustion engine and, via the shaft, drives the compressor impeller, which is arranged in the intake section of the internal combustion engine. This type of turbocharger is generally used to boost the power of internal combustion engines.
To regulate the turbine, the exhaust-gas flow which is passed through the turbine can be adjusted. A bypass is arranged on the turbine side for adjustment of the exhaust-gas flow, allowing at least some of the exhaust gas to be directed past the turbine. The quantity of diverted exhaust gas is regulated by a regulating mechanism, e.g. by a “waste gate valve” (or bypass valve). In certain conditions, this mechanism guides some of the exhaust gases through the bypass, around the turbine and directly into the exhaust. It is thereby possible, for example, to prevent an excessive rotational speed of the turbocharger and mechanical or thermal overloading of the internal combustion engine.
The regulating mechanism can be controlled by means of an actuator device. This generally comprises a control rod for transmitting force or movement within the regulating mechanism. There is a wide variety of design variants for coupling the control rod and the valve.
During the assembly of the turbocharger, the regulating mechanism is generally set manually. As is known from DE 10 2007 018 618 A1 or indeed from EP 1949926, the control rod can be coupled adjustably to the valve. This can be achieved, for example, by means of a thread on the control rod and a corresponding counterpart in the coupling mechanism (see FIG. 3). The problem with this procedure and this design is that there is no security against interference with the regulating mechanism. Thus, for example, the setting of the turbocharger can be changed by the end-user simply by adjusting the adjustable connection between the control rod and the coupling mechanism in order, for example, to achieve a higher engine power. In the event of damage to the turbocharger or to the internal combustion engine resulting therefrom, unauthorized modification, for example by the end-user, is very difficult to prove. Thus, damage arising from negligent action can lead to unjustified warranty claims. It is important to avoid such subsequent adjustment. Moreover, it is important to optimize the conditions for the installation and setting of a turbocharger, e.g. by improving the position and alignment of the regulating mechanism in respect of assembly and setting or fixing. This can allow the use of robots or other automation measures, for example. Another factor are the relatively high costs involved in producing the prior art solutions for adjustable regulating mechanisms by means of threaded rods or other screw-type solutions (see FIG. 3).